transaction: Add some missing flags for modules

transaction.go

@@ -138,6 +138,13 @@ const (
 	// ChangeExpiredAuthtok indicates that the authentication token
 	// should be changed if it has expired.
 	ChangeExpiredAuthtok Flags = C.PAM_CHANGE_EXPIRED_AUTHTOK
+	// PrelimCheck indicates that the password service should only
+	// perform preliminary checks. No passwords should be updated.
+	PrelimCheck Flags = C.PAM_PRELIM_CHECK
+	// UpdateAuthtok indicates that password service should update
+	// passwords Note: [pam.PrelimCheck] and [pam.UpdateAuthtok] cannot
+	// both be set simultaneously!
+	UpdateAuthtok Flags = C.PAM_UPDATE_AUTHTOK
 )
 
 // PutEnv adds or changes the value of PAM environment variables.

transaction.h

@@ -14,6 +14,14 @@
 #define BINARY_PROMPT_IS_SUPPORTED 0
 #endif
 
+#ifndef PAM_PRELIM_CHECK
+#define PAM_PRELIM_CHECK 0
+#endif
+
+#ifndef PAM_UPDATE_AUTHTOK
+#define PAM_UPDATE_AUTHTOK 0
+#endif
+
 #ifdef __sun
 #define PAM_CONST
 #else